Agitator for granular materials and the like



Sept. 20, 1966 P. LANGEN 3,273,761

AGITATOR FOR GRANULAR MATERIALS AND THE LIKE Filed Oct. 13, 1964 4 Sheets-Sheet l F/GJ INVENTOR P5751? Zfl/VG'E/V.

Sept. 20, 1966 P. LANGEN 3,273,76i

AGITATOR FOR GRANULAR MATERIALS AND THE LIKE Filed Oct. 13, 1964 v 4 Sheets-Sheet 2 Sept. 20, 1966 P. LANGEN 3,273,761

AGITATOR FOR GRANULAR MATERIALS AND THE LIKE Filed Oct. 13, 1964 L Sheets-Sheet 3 Sept. 20, 1966 P. LANGEN 3,273,761

AGITATOH FOR GRANULAR MATERIALS AND THE LIKE Filed Oct. 13, 1964 4 Sheets-Sheet 4 HIIHE' El INVENTOR PETER ZHNGE'JV fil 3.4:; 1.1L, Jl lwca/ ATTORNEY 13 (Ilaims. ci. 222386.5)

The present invention relates to devices for storing and dispensing granular, pulverulent and otherwise comminuted solid materials. More particularly, the invention relates to an agitator which may be installed in hoppers or the like to prevent bridging of accumulated material and to thereby promote controlled evacuation of such material.

It is already known to utilize agitators to prevent bridging of comminuted material in hoppers of underfeed stokers, in storage bins for flour, sand, ore, rock and the like, as well as in hopper wagons, hopper cars and analogous conveyances. In many instances, such agitators comprise a plate-like carrier, a diaphragm whose marginal portions are sealingly secured to the carrier and which is in contact with the material in a bin or the like, and a source of compressed fluid from which the fluid may be admitted into the space between the diaphragm and the carrier to expand the diaphragm whereby the latter exerts a certain pressure against the mass of comminuted material and breaks up any undesirable accumulations which might cause bridging or which otherwise tend to hinder control-led evacuation of material from the bin. The carrier is adjacent to and is placed flat against a flat side wall of the bin and, in many instances, the diaphragm is flattened out completely when the internal space of the agitator is not filled with a fluid pressure medium.

It was found that such mounting of the agitator is not entirely satisfactory, particularly because it happens quite frequently that the material tends to accumulate in the corners between pairs of mutually inclined side walls of a bin, hopper or analogous container. As a rule, the outflow of comminuted material along the inner side of each side wall in a hopper is such more satisfactory than the outflow of material in the corners between the side walls.

Accordingly, it is an important object of the present invention to provide an improved agitator which is capable of promoting controlled evacuation of granular, pulverulent or otherwise comminuted material in a manner which is much more satisfactory than the action of all such agitators of which I have knowledge at this time.

Another object of the invention is to provide a fluidoperated agitator of the just outlined characteristics wherein the flexible element is subjected to lesser stresses than the flexible element of a conventional diaphragmtype agitator for coal, rock, flour and similar flowable solid materials.

A further object of the invention is to provide an improved bin, hopper or analogous container which is equipped with one or more agitators of the above outlined general character.

An additional object of the invention is to provide an improved carrier for use in a fluid-operated agitator of the above outlined characteristics.

A concomitant object of the invention is to provide an agitator whose diaphragm-like flexible elements is much less likely to suffer minor or major damage in response to repeated and exceptionally strong contact with accumulations of flowable solid material.

Another object of my invention is to provide an agi- 3,273,761 Patented Sept. 20, 1966 tator which will operate satisfactorily and which is not likely to break down even though its fluid-admitting and evacuating system operates without any safety devices which are essential in many heretofore known agitators of this general character.

Still another object of the invention is to provide a specially con-figurated diaphragm-like flexible element which may be used with particular advantage in an agitator of the above outlined type.

A further object of the invention is to provide an agitator which is capable of subjecting comminuted solid material to at least some loosening stresses even when the diaphragm is in idle position.

Another object of the invention is to provide an a'gitator whose diaphragm is dimensioned, constructed and mounted in such a way that it automatically prevents or hinders adherence of comminuted material to its exposed surface.

Brie-fly stated, the invention resides in the provision of an apparatus for storing and dispensing granular and like comminuted materials. The apparatus comprises a container defining an internal space arranged to accommodate a supply of comminuted material and including two mutually inclined side walls having inner sides bounding an elongated corner zone of the internal space in which the material tends to agglomerate, and a novel agitator which comprises a flexible diaphragm preferably consisting at least in part of elastomeric material and extend ing across a portion of the corner zone to define with the side walls a fluid-receiving chamber. The agitator further comprises means for admitting a fluid into the chamber to flex the diaphragm against the material in the internal space of the container and to thus break up eventual agglomerations in the corner zone.

Preferably, the edge portions of the diaphragm are sealingly secured to the marginal portions of a rigid carrier having two mutually inclined sections or panels each of which is secured to the inner side of one of the side walls, and such panels may be reinforced by stitfeners which are inclined with reference to the corner zone. The stiffeners increase the resistance of the respective panels in a direction toward the corner zone.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved agitator itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of a specific embodiment with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic perspective view of a container comprising a plurality of agitators which are con structed in accordance with the present invention;

FIG. 2 is an enlarged horizontal section through a corner portion of the container and through one of the agitators, substantially as seen in the direction of arrows from the line II-II of FIG. 1;

FIG. 3 is a fragmentary vertical section as seen in the direction of arrows from the line IIII'II of FIG. 2; and

FIG. 4 is a top plan view of the agitator, substantially as seen in the direction of the arrow IV in FIG. 3.

Referring to the drawings, and first to FIG. 1, there is shown the lower portion of a storage container or bin "1 which accommodates a supply of coal, rock, sand, flour :order flowable comminuted solid material. The container comprises a bottom portion 2 which constitutes a hopper and comprises four inwardly and downwardly inclined side Walls converging toward a discharge opening or outlet 3. This hopper accommodates a plurality of agitators which are constructed in accordance with the present invention. FIG. 1 shows that the hopper 2 acoommodates two agitators, but it is often suflicient to provide the hopper with a single agitator or to provide this hopper with as many as three or even four agitators. The left-hand agitator 4 is mounted in the corner zone between the side walls 5, 6 and the right hand agitator 7 is mounted in the corner zone between the side walls 6 and 8. The two agitators are of identical construction and, therefore, it suffices to describe in full detail one of them, namely, the agitator 4 whose construction is illustrated in FIGS. 2, 3 and 4.

FIG. 2 shows that the agitator 4 comprises a rigid V- shaped carrier 410 including a left-hand section or panel 111 which is adjacent to the inner side of the side wall and a right-hand section or panel 12 which is adjacent to the inner side of the side wall 6. The sections '11, 12 are connected by a flat back section or web 13 which extends across the corner zone '14 between the mutually inclined side walls 5 and 6. Each of the sections 11, 12 is of polygonal outline and resembles a trapezium or trapezoid, but it is equally possible to use a carrier whose sections are triangular, semicircular or semielliptical. The marginal portions of the sections '11, .12 are provided with inner clamping rails 15 which are welded thereto and which cooperate with outer clamping rails 16 to engage the opposite sides of the edge portions 18 on a deformable flexible element 17 (hereinafter called diaphragm) of rubber or other elastomeric material. Each edge portion 118 is provided with a bead or end zone 19 which extends outwardly beyond the adjacent portions of the clamping rails :15, 16 to abut against the inner side of the side wall 5 or 6. The clamping rails 15, 16 are connected by bolts 20 which extend through the edge portions 18 so that the diaphragm is sealingly retained between the rails to prevent uncontrolled escape of compressed air or another suitable pressure medium which may be admitted into the internal chamber 21 of the agitator 4. The outer clamping rails 16 are provided with brackets 22 which are secured to the side walls 5, '6 by bolts 23, for example, by bolts known as expansion anchors. It will be seen that the beads 19 form a fluidtight seal around the sections 11,12 by abutting against the inner sides of the walls 5, 6 so that the outer sides of the sections may remain slightly spaced from such walls. The diaphragm 17 extends across the corner zone 14.

The side wall 5 is provided with a bore which accommodates the discharge end of a supply conduit 24 serving to admit compressed fluid from a suitable source, for example, an air compressor 25 or the like. The conduit contains a shutofi valve 26 of any known design. The section 11 is provided wit-h an aperture 27 which registers with the discharge end of the conduit '24, and the latter is preferably provided with an annular flange which is bolted to the section 1 1 and/or to the side wall 5. The side wall 5 is further provided with a second bore 28 which serves to allow for evacuation of pressure fluid and is connected with a discharge conduit 29 including a valve 30 of any known design.

In the illustrated embodiment, the agitator 4 comprises a safety valve 31 which is mounted at the intake end of the bore 28 and may be caused to open in a fully automatic Way in response to a predetermined maximum pressure in the chamber 21. The means for opening the valve 311 in response to such maximum pressure comprises a series of cord-like or cable-like actuating elements 32 which are connected to space-d portions of the diaphragm 17 and at least one of which will open the safety valve 31 when the corresponding portion of the diaphragm is deformed beyond the phantom-like position 17'. The exact construction of the safety valve 31 forms no part of the present invention. "For example, a satisfactory safety valve for use in the agitator 4 and/ or 7 is disclosed in my US. Letters Patent No. 3,121,500 which is assigned to the same assignee.

Since the diaphragm 17 is preferably designed to transmit very high pressures which are necessary to break up agglomerations of flowable material in the internal space 33 of the hopper 2 when the diaphragm is flexed by fluid which is admitted into the chamber 21, the metallic material of the sections 11, 12 could undergo deformation in response to a pull exerted against such portions of the inner clamping rails 15 which extend between the brackets 22. In order to avoid such deformation of the carrier 10, I prefer to provide the sections 11, 1'2 with one or more elongated horizontal or inclined stiifeners in the form of tubular ribs 34 one of which is shown in FIG. 2. FIGS. 3 and 4 show that the carrier may be provided with several stiffening ribs 34, depending on the dimensions of the agitator, on the thickness of the sections, on the material of the sections, on the nature of material which is being stored in the internal space 33, on the pressures prevailing in the chamber 21, and on certain other factors. The cross sections of the ribs 34 increase toward the web 13 where the carrier 10 is subjected to highest bending stresses, and the ribs are inclined at least slightly with reference to the longitudinal direction of the corner zone 14. Thus, the resistance which the panels 11, 12 offer to the flexing action of fluid in the chamber 21 increases toward the web 13. If desired, the sections 11, .12 may consist of corrugated metallic stock, and it is equally possible to provide such sections with additional stiffeners in the form of vertical or nearly vertical ribs which are parallel with the web 13. The beads 19 seal the internal space 33 from the aperture 27 and bore 28.

The diaphragm 17 is preferably dimensioned in such a way that, when the valve 30 is open and the chamber 21 is empty, the inner side of the diaphragm is of concave shape, see FIG. 2, whereby the outer side of the diaphragm may but need not overlie the stiffening ribs 34. An important advantage of such dimensioning of the diaphragm is that the latter undergoes substantial expansion only at the time when it has been caused to move beyond the phanton-line position 17. In other words, during its movement from the idle position 17 to the position 17', the diaphragm is not subjected to substantial stresses which would tend to exert thereon a pull in the plane of its material. Consequently, the diaphragm will be capable of transmitting stresses exceeding substantially such stresses which are transmitted by a diaphragm which is maintained under initial tension. The ribs 34 prevents complete collapse of the diaphragm 17 even if the latter is subjected to substantial deforming stresses by contact with flowable material which fills the space 33. Therefore, the diaphragm cannot overlie completely the inner sides of the sections 11, 12 and the fluid which enters through the aperture 27 will be free to flow to all or nearly all zones of the chamber 21 to act against the outer side of the diaphragm and to move it to the position 17 whenever necessary, i.e., whenever the operator desires to insure controlled evacuation of material through the outlet 3 of the hopper 2. Also, when the diaphragm is in the full-line position of FIG. 2 and is in contact with the material which fills the space 33, certain of its portions are pressed into the spaces between the ribs 34 whereby the diaphragm is subjected to some tension and exerts a corresponding force upon the material to prevent or to reduce oak-ing along the inner side of the diaphragm.

It is to be noted that, though the drawings illustrate a safety valve 31, such valve is not absolutely necessary because the diaphragm begins to undergo substantial expansion only at the time it moves beyond the phantom-line position 17' of FIG. 2. In agitators of the type disclosed in my aforementioned Letters Patent No. 3,121,500, the diaphragm begins to expand immediately after it starts to move from the idle position. In such agitators, the safety valve serves to prevent damage to the diaphragm when the resistance of the adjacent batch of comminuted material decreases suddenly and when the fluid in the internal.

chamber of the agitator is free to expand without any or with minimal opposition on the part of comminuted material. For example, when the material which is accommodated in the storage container tends to agglomerate or to form a bridge which opposes the expansion of the diaphragm, and when the operator continues to admit compressed air into the internal chamber of the agitator, the material at the inner side of the diaphgram often yields quite suddenly and allows for rapid expansion of the diaphragm. If the diaphragm is not strong enough and/or if the internal pressure in the agitator happens to be very high, the diaphragm will be destroyed as soon as the material yields and begins to break up to be evacuated through the outlet of the storage container.

The likelihood of such destruction of the diaphragm is practically non-existent when the diaphragm is mounted between two mutually inclined sections 11, 12 of a rigid carrier. This will be readily understood upon perusal of the preceding description since, on moving to the position 17', the diaphragm has transmitted to the material in the space 33 a substantial loosening or shifting force without, however, as yet undergoing any appreciable expansion. In other words, in the position 17', the diaphragm is mirror symmetrical to the full-line position of FIG. 2 and, therefore, the diaphragm can withstand substantial expansion before its material reaches the limit of elasticity.

The agitator 4 is operated as follows:

When the material is entrapped in the space 3 3 and the outlet 3 is closed, the agitator need not be put to use. The valves 26, 30 and 31 are closed, and the diaphragm 17 is in the full-line position of FIG. 2. The material in the hopper 2 presses against the inner side of the diaphragm and causes it to yield into the spaces between the stiffening ribs 34.

If the operator thereupon exposes the outlet 3- and notices that the material refuses to flow freely, he opens the valve 26 and starts the compressor so that the chamber 21 is gradually filled with compressed air. The diaphragm 17 begins to move toward the position 17' and exerts upon the material in the space 33 a pressure which, sooner or later, is bound to break down the resistance of such material and promotes regular outflow through the outlet 3. Should the diaphragm expand beyond the position 17', at least one of the cords 32 will open the safety valve 3 1 so that air filling the chamber 21 may escape through the discharge conduit 29. The operator opens the valve at the time he starts the compressor 25. The valve 3-1 closes automatically when the diaphragm 1-7 returns to the position 17',

It is preferred to construct the diaphragm 17 in such a way that the median port-ion 17a is somewhat thicker than the remainder of the diaphragm. Such median portion 170: of greater thickness preferably extends in the longitudinal direction of the corner zone 14. -By making the median portion 171 thicker, I insure that the diaphragm can withstand stresses which are transmitted thereto by comminuted material when the agitator is not in use. Thus, the fact that the median portion 17a may be deformed between the ribs 34 is of no consequence insofar as the durability of the diaphragm is concerned. Also, the diaphragm may be reinforced :by inserts in the form of filaments or in any other suitable way. The filaments 40 are embedded in the elastomeric material of the diaphragm and are inclined with reference to the corner zone 14.

When the agitators of my invention are installed in a storage container which comprises a hopper or a similar discharging device having pairs of mutually inclined side walls, the agitators will be mounted in the corner zones between the side Walls. However, it is to be noted that the agitators of my invention are quite useful in containers which comprise vertical or nearly vertical side Walls. By placing the diaphragms in the corner zones between adjoining walls, I insure that the agitators will break up agglomerations in places which are most likely to allow for the formation of such agglomerations.

Finally, it is to be noted that the diaphragm need not be a flat body of flexible material. Thus, the diaphragm may be formed in such a way that it automatically tends to resemble a cup, such as is shown at 17 in FIG. 2, even when its material is in unstressed condition. Such cupshaped diaphragms as well as the diaphragm of FIGS. 2-4 will be capable of subjecting the material in the space 33 to substantial loosening stresses without undergoing any appreciable expansion. In contrast, a diaphragm of the type disclosed in my aforementioned Patent No. 3,121,500 normally begins to expand as soon as it starts to move from the idle position in which it lies substantially flat against its carrier. Also, a diaphragm which begins to expand as soon as it starts to move from the idle position requires higher pressures in the internal chamber of the agitator because the pressure of compressed air must overcome not only the resistance which is offered by the material in the storage container but also the resistance which the material of the diaphragm offers to expansion. Such resistance to expansion is offered by the diaphragm 17 only at the time it reaches the phantom-line position 17' of FIG. 2.

If the diaphragm 17 is provided with reinforcing inserts, for example, with filaments 40 of the like, the reinforcing elements are preferably inclined with reference to the zone of maximum expansion of the diaphragm, i.e., with reference to the corner zone 14. In all embodiments of my invention, the diaphragm may be dimensioned in such a way that it is maintained under some initial tension along the corner zone 14.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute the generic and specific aspects of the present invention and, therefore, such adaptations would and are intended to be comprehended within the meaning and range of equivalence of the following claims,

What is claimed as new and desired to be secured by Letters Patent is:

1. For use in a container for comminuted material having at least one pair of mutually inclined side Walls bounding a container corner zone in which the material tends to agglomerate, an agitator for said corner zone comprising a rigid carrier having two mutually inclined sections bounding a section corner zone, a flexible diaphragm having edge portions sealingly secured to the corresponding sections and extending across said section corner zone to define with the carrier a fluid-receiving cham ber, and means for admitting a fluid into said chamber to flex the diaphragm; and means for securing said sections to the inner faces of said mutually inclined side walls of a container, so as to overlie said container corner zone, whereby said agitator breaks up eventual agglomeration of material in said section corner zone when said diaphragm is flexed in response to admission of fluid into said chamber.

2. A structure as set forth in claim 1, wherein said diaphragm comprises a layer of elastomeric material and reinforcing inserts embedded therein, and wherein said reinforcing inserts are filaments which are inclined with reference to said section corner zone.

3. In an apparatus for storing and dispensing granular and like comminuted materials, in combination, a container defining an internal space arranged to accommo date a supply of comminuted material, said container comprising two mutually inclined side walls having inner sides bounding an elongated corner zone of said internal space in which the material tends to agglomerate; and an agitator comprising a rigid carrier having two mutually inclined panels each secured to the inner side of one of said walls so that said carrier bounds at least a portion of said corner zone, a flexible diaphragm having edge portions sealingly secured to said panels and a median portion extending across said corner zone, said diaphragm and said panels defining between themselves a fluid-receiving chamber, and means for admitting a fluid into said chamber through one of said side walls and through one of said panels to flex the diaphragm against the material in said internal space and to break up eventual agglomerations in said corner zone.

4. In an apparatus for storing and dispensing granular and like comminuted materials, in combination, a container defining an internal space arranged to accommodate ,a supply of comminuted material, said container comprising tWo mutually inclined side walls having inner sides bounding an elongated corner zone of said internal space in which the material tendsto agglomerate; and an agitator comprising a rigid carrier having two mutually inclined panels each secured to the inner side of one of said walls so that said carrier bounds at least a portion of said corner zone, a flexible diaphragm having edge portions sealingly secured to said panels and a median portion extending across said corner zone, said diaphragm and said panels defining between themselves a fluid-receiving chamber and said diaphragm having a concave side which is in contact with the material in said internal space when the chamber is empty, and means for admitting a fluid into said chamber through one of said side walls and through one of said panels to flex the diaphragm against the material in said internal space and to break up eventual agglomerations in said corner zone.

5. A structure as set forth in claim 4, wherein said diaphragm consists of elastomeric material and wherein said median portion is dimensioned in such a way that it -is maintained under some initial tension along said corner zone.

6. A structure as set forth in claim 4, wherein said me- .dian portion resembles a cup when the diaphragm is in unstressed condition.

7. in an apparatus for storing and dispensing granular and like comminuted materials, in combination, a container defining an internal space arranged to accommodate a supply of comminuted material, said container comprising two mutually inclined side walls having inner sides bounding an elongated corner zone of said internal space in which the material tends to agglomerate; and an agitator comprising a rigid carrier having two mutually inclined panels each secured to the inner side of one of said walls so that said carrier bounds at least a portion of said corner zone, said panels comprising elongated stiffeners which are inclined with reference to said corner zone, a flexible diaphragm having edge portions sealingly secured to said panels and a median portion extending across said corner zone, said diaphragm and said panels defining between themselves a fluid-receiving chamber, and means for admitting a fluid into said chamber through one of said side walls and through one of said panels to flex the diaphragm against the material in said internal space and to break up eventual agglomerations in said corner zone.

8. A structure as set forth in claim 7, wherein said stiffeners are dimensioned in such a way that the resistance of said panels to the flexing action of fluid in said chamber increases in a direction toward said corner zone.

9. In an apparatus for storing and dispensing granular and like comminuted materials, in combination, a container defining an internal space arranged to accommodate a supply of comminuted material, said container comprising two mutually inclined side walls having inner sides bounding an elongated corner zone of said internal space in which the material tends to agglomerate; and an agitator comprising a rigid carrier having two mutually inclined panels each secured .to the inner side of one of said Walls so that said carrier bounds at least a portion of said corner zone, a flexible diaphragm having edge portions sealingly secured to said panels and a median portion extending across said corner zone, said diaphragm and said panels defining between themselves a fluidreceiving chamber, means for admitting a fluid into said chamber through one of said side Walls and through one of said panels .to flex the diaphragm against the material in said internal space and to break up eventual agglomerations in said corner zone, and valved conduit means communicating with said chamber to permit controlled evacuation of fluid.

10. A structure as set forth in claim 9, wherein said panels are of polygonal outline and further comprising clamping means secured to said panels and engaging the opposite side of said edge portions.

11. A structure as set forth in claim 9, wherein said container is a hopper having a lower end provided with an outlet and wherein said side Walls are inclined downwardly and inwardly toward said outlet.

12. A structure as set forth in claim 9, wherein said fluid is compressed air and wherein said fluid admitting means comprises a source of compressed air and a valved supply conduit connecting said source with said chamber.

13. In an apparatus for storing and dispensing granular and like comminuted materials, in combination, a container defining an internal space arranged to accommodate a supply of comminuted material, said container comprising pairs of mutually inclined side walls having inner sides bounding at least two corner zones of said internal space in which the material tends to agglomerate; and an agitator for each of said corner zones, each agitator comprising a rigid carrier having two mutually inclined sections secured to the inner sides of the respective pair of walls, a flexible diaphragm having edge portions sealingly secured to the corresponding sections and extending across the respective corner zone to define with the corresponding carrier a fluid-receiving chamber, and means for admitting a fluid into each of said chambers to flex the respective diaphragms against the material in said internal space and to break up eventual agglomerations in the respective corner zones.

References Cited by the Examiner UNITED STATES PATENTS 2,968,425 1/1961 Paton 222- 3,158,296 11/1964 Cornelius 222-386.5 3,170,600 2/1965 Pierson 222-195 X 3,202,461 8/1965 Paton 222-493 X ROBERT B. REEVES, Primary Examiner.

STANLEY H. TOLLBERG, Examiners. 

1. FOR USE IN A CONTAINER FOR COMMINUTED MATERIAL HAVING AT LEAST ONE PAIR OF MUTUALLY INCLINED SIDE WALLS BOUNDING A CONTAINER CORNER ZONE IN WHICH THE MATERIAL TENDS TO AGGLOMERATE, AN AGITATOR FOR SAID CORNER ZONE COMPRISING A RIGID CARRIER HAVING TWO MUTUALLY INCLINED SECTIONS BOUNDING A SECTION CORNER ZONE, A FLEXIBLE DIAPHRAGM HAVING EDGE PORTIONS SEALINGLY SECURED TO THE CORRESPONDING SECTIONS AND SEXTENDING ACROSS SAID SECTION CORNER ZONE TO DEFINE WITH THE CARRIER A FLUID-RECEIVING CHAMBER, AND MEANS FOR ADMITTING A FLUID INTO SAID CHAMBER TO FLEX THE DIAPHRAGM; AND MEANS FOR SECURING SAID SECTIONS TO THE INNER FACES OF SAID MUTUALLY INCLINED SIDE WALLS OF A CONTAINER, SO AS TO OVERLIE SAID CONTAINER CORNER ZONE, WHEREBY SAID AGITATOR BREAKS UP EVENTUAL AGGLOMERATION OF MATERIAL IN SAID SECTION CORNER ZONE WHEN SAID DIAPHRAGM IS FLEXED IN RESPONSE TO ADMISSION OF FLUID INTO SAID CHAMBER. 